中文摘要：

从长期受PAHs污染的土壤中分离得到一株菲降解菌B4一氧化节杆菌（Arthrobacter oxydans）．对其菲耐受能力及降解性能进行了考察，结果表明，该菌在有氧环境中能够耐受2000mg／L的菲，并对菲具有显著降解作用．当无机盐培养液中菲初始质量浓度为50mg／L，134投菌量为20g／L（湿重，含水率：94．55％），菌龄为48h，pH为7．0～8．0时，5d内菲降解率为60％左右．通过原子力显微镜对菲降解前后菌体表面形态进行观察，结果显示，菲对该菌株存在一定毒性，随着作用时间的增加，细胞形态明显发生改变，其表面超微结构也趋于复杂．

英文摘要：

A phenanthrene-degrading bacterium, Arthrobacter oxydans B4 which can grow in with a high concentration of phenanthrene has been isolated from a long-term PAHs-contaminated soil. The tolerance of strain B4 to phenanthrene and its biodegradation characteristics were studied. The results showed that the strain B4 in the aerobic environment was able to tolerate phenanthrene as high concentration as 2.000 mg/L, and it had a significant efficiency of phenanthrene degradation. The degradation rate of phenanthrene reached about 60% within 5 days when the initial concentration of phenanthrene in mineral salts medium （MSM） was 50 mg/L, the inoculum dosage was 20 g/L （wet weight, moisture content： 94. 55% ）, the cell age was 48 h and pH was 7.0 -8.0. Atomic force microscopy was applied to observe the surface morphology of strain B4 before and after biodegradation. The results demonstrated that phenanthrene had toxicity on B4. The cell morphology significantly changed and its ultrastructure was also complicated as reaction time increased.